Growing Tomatoes in a Greenhouse: A Complete Guide for Maltese Gardeners

Growing tomatoes under cover is one of the most rewarding ways to raise fresh, flavoursome produce at home. A suitable greenhouse can extend the productive period, shelter plants from harsh weather and give you greater control over heat, watering and ventilation. This guide explains, step by step, how to cultivate tomatoes successfully in Malta and why a Bloomcabin aluminium greenhouse with polycarbonate panels can create an excellent growing environment.

Why grow tomatoes in a greenhouse?

Malta’s sunny conditions can still bring strong winds, intense heat and occasional cool spells. A greenhouse offers tomato growers several advantages:

• Longer season – sow earlier and continue harvesting later.
• Stable microclimate – tomatoes perform best with steady temperatures and fewer sudden changes.
• Protection from rain, wind and pests – helping to prevent disease and physical damage.
• Better yields and fuller flavour – through balanced light, warmth and moisture.

Another benefit is control throughout the growing process: from sowing and potting on to watering, pollination and picking the final fruit.

10 tips for successful greenhouse tomatoes

1. Choose the right variety

For greenhouse cultivation, choose tall-growing indeterminate varieties, which keep producing fruit over a long period. Popular choices include:

• Sungold – a sweet orange cherry tomato with early crops.
• Gardener’s Delight – reliable, robust and well suited to beginners.
• Moneymaker – a productive, established standard variety.
• San Marzano – fleshy and low in seeds, ideal for sauces.

For smaller greenhouses or container growing, choose determinate bush tomatoes such as Roma or Balconi Red, which remain more compact.

2. Use nutrient-rich soil

Tomatoes are hungry plants and need loose, humus-rich soil that retains water well. Combine garden soil with compost, sand and, where useful, perlite to improve aeration. A pH value of 6.0 to 6.8 is also important.

3. Time planting carefully

Start plants indoors in late winter. Move young plants into the greenhouse when night temperatures remain consistently above 10 °C – the timing varies across the Maltese Islands. During an unusually cool spell, earlier planting may require horticultural fleece.

4. Support and maintain plants

Tomatoes need structure and regular care:

• Support plants with bamboo canes, tomato spirals or strings.
• Remove side shoots regularly to keep the plant upright.
• Cut away lower leaves once they turn yellow to improve airflow.

These measures encourage fruiting and help reduce disease.

5. Encourage pollination

Pollinating insects can be scarce under cover. Help by hand:

• Gently shake flower trusses in the morning.
• Alternatively, use a soft brush or electric toothbrush.

Regular pollination supports even fruit formation.

6. Water consistently

Regular watering is essential:

• Water early in the morning, directly at the roots.
• Avoid wet foliage to reduce fungal risk.
• Ideally, install drip irrigation for consistent moisture.

Irregular watering can cause blossom-end rot or split fruit.

7. Feed correctly

Tomatoes need plenty of potassium for fruit development. From the first flowers:

• Feed every 10–14 days with tomato fertiliser.
• Alternatively, use nettle or comfrey liquid feed.

Avoid overfeeding, which produces leaves rather than fruit.

8. Monitor temperature and humidity

Tomatoes grow best at:

• Day: 21–26 °C
• Night: above 13 °C
• Humidity: 60–70 %

Excess humidity encourages mould. Provide good ventilation and, if needed, air circulation with fans.

9. Spot diseases and pests

Check plants regularly for:

• Aphids – especially on young shoots
• Whiteflies – beneath leaves
• Grey mould – particularly in humid conditions
• Powdery mildew – white growth on leaves

Use yellow sticky traps, biological controls or a treatment whose current Maltese label covers tomatoes and the intended use.

10. Harvest at the right time

Pick tomatoes when fully coloured but still firm. Daily checks pay off: regular harvesting encourages more fruit and prevents overripening.

Common problems and solutions

Problem	Cause	Solution
Blossom-end rot	Calcium shortage, uneven watering	Water regularly; use calcium products
Distorted leaves	Heat stress, unsuitable feeding	Provide shade; adjust feeding
Grey mould	High humidity, insufficient air circulation	Ventilate more; remove affected plant parts
Yellow leaves	Nutrient shortage or overwatering	Feed evenly; avoid waterlogging

Why a Bloomcabin greenhouse suits tomatoes

Bloomcabin aluminium greenhouses with polycarbonate panels combine stability, light transmission and weather protection for tomato growing. For Malta’s strong sun and wind, select the model and site carefully and seek a site-specific structural assessment where appropriate.

Robust, low-maintenance construction

Corrosion-resistant aluminium profiles, straightforward assembly and high wind and snow-load capacity provide durable, dependable use over many years.

High-quality polycarbonate panels

• UV-resistant and shatter-resistant
• Diffused light helps protect against sun scorch
• Insulating properties help retain warmth during temperature changes

Intelligent ventilation options

Every model has roof windows, with automatic openers available as an option. This helps maintain a suitable greenhouse climate.

Flexible for every garden

Whether you have an urban courtyard, a townhouse garden or a rural plot, Bloomcabin offers sizes and models for different needs.

Start growing your own tomatoes

With a Bloomcabin greenhouse, you can create a productive setting for flavoursome, healthy home-grown tomatoes.

Explore our aluminium greenhouse range now – ideal for home gardeners throughout the Maltese Islands.

Bloomcabin – where garden quality, function and style come together.